The present invention generally relates to a collating arrangement for a copying apparatus and the like and more particularly, to a sorter which classifies copy paper sheets fed out of a copying apparatus for accommodation thereof onto respective rays.
Generally, in a copying apparatus, for example, an electrophotographic copying apparatus, it is so arranged that an image of an original document is formed on a photosensitive member, i.e., a photoreceptor as a visible toner image, which is then transferred onto copy paper sheets sequentially fed, and the copy paper sheets thus transferred with the toner image are thereafter passed through a fixing station so as to be subsequently discharged out of the copying apparatus. The copied paper sheets thus discharged are normally received on a tray or the like. In the above case, however, when a large number of original documents are simultaneously copied for multi-copying, it is necessary to effect collating of pages after copying.
In order to eliminate such a troublesome procedure for collating, there has conventionally been proposed for actual application, an arrangement in which a sorter is coupled to a copy paper sheet discharge port of a copying apparatus, thereby to sequentially classify and accommodate the copy paper sheets after completion of the copying, onto respective trays constituted in a plurality of stages.
In the sorter as referred to above, there is one type which is adapted to be driven and controlled according to instructions from the copying apparatus main body, and another type which is arranged to detect discharged copy paper sheets independently by the sorter itself for driving and control thereof. The sorter of the former type is formed into one unit with the copying apparatus, and is so constructed that, although the sorter itself may be separated from the copying apparatus, copy operation can not be effected unless the sorter has been mounted onto said copying apparatus. On the contrary, since the sorter of the latter type does not have a particular interface with respect to the copying apparatus main body, it can be very easily separated from the copying apparatus, thus remarkably improving exchangeability of trays in the normal applications.
However, although the sorter which is not provided with the interface between said sorter and the copying apparatus can readily cope with alterations in the number of paper sheets to be copied, if paper jamming or running out of copy paper sheets takes place at the side of the copying apparatus main body, transport time interval between copy paper sheets becomes longer than a predetermined time interval, and therefore, the uppermost tray is selected so as to guide following copy paper sheets successively onto subsequent trays for accommodation. In other words, if the transport time interval between the copy paper sheets which are being fed, exceeds the predetermined time interval, the sorter main body effects control to select the uppermost tray. However, if the prolonged transport time interval results from any troubles at the side of the copying apparatus main body, there is a problem in resetting to the uppermost tray. Therefore, it has been a common practice to manually select the trays after remedy of the troubles in the copying apparatus main body so as to guide and accommodate copy paper sheets successively fed, onto the trays at proper places. In this manner, the sorter which is not provided with the interface requires the procedure as described above, which is very troublesome and inconvenient.